Here is some examples of simple supports for army and fleet :
In next diagram, the French army in Gascony (gas) supports the army in Marseilles (mar) to Burgundy (bur). The German army in Burgundy will be dislodged :
In next diagram, the German army in Silesia (sil) is supported by the fleet in the Baltic (BAL) in pushing the Russian army out of Prussia (pru) :
Note that the German army and fleet are both adjacent to the target province (Prussia) but not to each other. A unit does not have to be adjacent to the unit it is supporting. However, it must be next to the province into which it is giving support and must be able to legally move there itself.